The present invention relates to a process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus.
The electrophotographic image forming apparatus forms an image on a recording material through an electrophotographic image-formation-type process. Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (a laser beam printer or mountable LED printer), a facsimile machine, a word processor, and the like.
The process cartridge integrally contains an electrophotographic photosensitive drum, and charging means, developing means or cartridge, in the form of a unit or a cartridge, which is detachably mountable to a main assembly of an image forming apparatus. The process cartridge may contain the electrophotographic photosensitive drum, and at least one of charging means, developing means and cleaning means, in the form of a cartridge that is detachably mountable to the main assembly of the image forming apparatus. Furthermore, the process cartridge may contain at least the electrophotographic photosensitive drum and the developing means.
Heretofore, in an electrophotographic image forming apparatus using the electrophotographic image process, a process-cartridge type is a type in which the electrophotographic photosensitive member and process means, actable on the electrophotographic photosensitive member, are integrally contained in a cartridge, which is detachably mountable to the main assembly of the image forming apparatus. In such a process-cartridge type, the maintenance of the apparatus can be carried out by the users without servicemen, and therefore, the operativity can be improved significantly, and for this reason, it is widely used in image forming apparatus.
An example of such a process cartridge includes a toner-developing frame having a developing frame supporting developing means and a toner-developing frame having a toner container accommodating the toner, and a cleaning frame rotatably supporting the photosensitive drum and having cleaning means, wherein the toner developing frame and the cleaning frame are coupled such that they are pivotable relative to each other about an axis parallel with the photosensitive drum. The process cartridge further includes an urging member for urging the photosensitive drum and the developing roller of the developing means toward each other.
The present invention provides further developments.
Accordingly, it is a principal object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus wherein the positional relation between an electrophotographic photosensitive drum and a developing roller can be correctly maintained.
It is another object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus wherein the positional relation between a developing roller and an electrophotographic photosensitive drum can be correctly maintained, in which no additional cleaning means is used.
According to an aspect of the present invention, there is provided an electrophotographic image forming apparatus and a process cartridge usable therewith comprising an electrophotographic photosensitive drum;
a developing roller for developing an electrostatic latent image formed on the electrophotographic photosensitive drum with a developer;
a frame for rotatably supporting the electrophotographic photosensitive drum;
a supporting member, rotatably supported in the frame, for rotatably supporting the developing roller at a position away from a rotational center thereof; and
an urging member for elastically urging the frame to urge the developing roller toward the electrophotographic photosensitive drum.